Winterize question. I have a 2010 355QBQ. I have never done the winterize on it. I have always taken it to an RV dealer. This year however, the price had gone up to $107. Seems pretty high. Anyone out there with this unit done the winterizing on their own that can instruct me on how to do it?

First drain low point drains.
Drain water heater.
Bypass water heater.
Remove interior water filter and place canister back on.

If you have the winterize option then turn that on to suck the antifreeze out of the jugs "you'll need 4 gallon"

Run furthest tap first hot and cold till good and pink, then work your way closest to where water station is.
Dump a cup or two of antifreeze in each drain.
Don't forget to put some on top of the toilet seal.
Also don't forget outside shower if applicable.

Just like Turbs said, but also remember the Spray Ports if you haven them, along with outside kitchen and washer and dryer preps. Drain all low points. Front, rear and your fresh water tank. You should have a hose that will pull out from the docking station. Look down under the water filter and you will see a valve. Turn it to off, take cap off of hose and put it into antifreeze. Turn on water pump and pump the pink stuff through all lines.

In the past I used five gallons or so. It usually took about 3.5 for the pressure side of the system, the half gallon I'd pour down the traps just to make sure, a gallon into the black tank to mix with what was already there, and I'd leave a couple of cups worth on the flush valve to keep it moist.

I imagine the 5er will take about the same, I'll get an extra gallon because I have a water filter and washer lines in the bedroom then adjust next year.